RockWoofFound alongside
Fluorite
Mohs 4. Cubes in purple, green or yellow; many glow under UV. Mindat
13 sites
Gold
Mohs 2.5–3. Soft, heavy and bright yellow; it doesn’t tarnish. Mindat
6 sites
Silver
Mohs 2.5–3. Native silver tarnishes black. Mindat
6 sites
Feldspar
Mohs 6–6.5. Blocky crystals with flat cleavage faces. Mindat
2 sites
Pyrite
Mohs 6–6.5. Brassy “fool’s gold,” often cubic. Mindat
2 sites
Beryl
Mohs 7.5–8. Six-sided crystals; aquamarine and emerald are beryl. Mindat
1 site
Counts are sites whose USGS record mentions the mineral or commodity. Hardness from Mindat.
By county
Lawrence County (10) · Custer County (2) · Pennington County (1)
Sites
| Site | Commodity | Minerals recorded | Status | Approx. location |
|---|---|---|---|---|
| Hugo Mine | Feldspar, Mica, Beryllium, Lithium | Amblygonite, Beryl, Muscovite, Spodumene | Past Producer | 43.882, -103.423 |
| Pennsylvania Mine | Gold, Silver | Calaverite, Gold, Silver | Past Producer | 44.359, -103.802 |
| Echo Mine | — | Fluorite | Occurrence | 44.386, -103.811 |
| Ulster Mine | Gold | Fluorite | Past Producer | 44.363, -103.886 |
| Ross Hannibal Group | Gold, Silver | Fluorite | Past Producer | 44.323, -103.801 |
| Hardscrabble Mine | Gold, Silver | Fluorite, Gold, Silver | Past Producer | 44.329, -103.825 |
| Hidden Treasure Group Mine | Gold, Silver | Fluorite, Gold, Silver | Past Producer | 44.359, -103.811 |
| American Mining Company | Gold, Silver | Gold, Silver | Past Producer | 44.371, -103.900 |
| Hidden Treasure Lode | Feldspar | — | Past Producer | 43.616, -103.542 |
| Big Spar Mine | Fluorine-Fluorite | — | Producer | 43.761, -103.653 |
| Wolf Prospect | — | — | Prospect | 44.359, -103.814 |
| False Bottom Prospect | — | — | Occurrence | 44.371, -103.829 |
| Echo | Fluorine-Fluorite | — | Unknown | 44.387, -103.809 |
Back to Rockhounding in South Dakota.
How we built this page: we counted named sites in the USGS Mineral Resources Data System (MRDS) for this area, left out sand, gravel, crushed stone, clay pits and unnamed sites, grouped them by Census county, and linked every site to its USGS record. We did not visit these sites, and MRDS does not tell you who owns the land or whether collecting is allowed.
Source: USGS Mineral Resources Data System (MRDS). USGS ceased systematic updates to MRDS around 2011, so status and details may be out of date. Each site links to its USGS record.
Updated